During the coming year we propose to complete the studies of human CSF cells in various CNS disease and characterization of the Ia positive cells in mice with Sindbis-virus encephalitis. We will then begin our studies of B lymphocyte entry into the CNS by determining the necessity for T cells to be there first using athymic nude mice and the stage of differentiation of B cells when they come into the CNS from peripheral blood using various B cell tumor lines and immunocytochemistry. Additional attempts will be made to localize measles virus in mononuclear blood cells from acute cases. We will attempt to study incubating cases, i.e., the younger siblings of index measles cases. We will also determine the proportion of viral genomic versus messenger RNA in a variety of animal and in vitro models of measles virus infection. We hope to determine whether certain non-productive infections can be explained by a defect on the production of full genomic length viral RNA. The biology of LV-IFN will include experiments on restriction of virus replication using DNA hybridization and on induction of Ia antigens. Ia antigen expression in macrophages will be evaluated using monoclonal antibodies to this protein in immunocytochemical tests in a FACS analysis system or in cytocentrifuged preparations using ABC immunoperoxidase. With elutriation pure populations of monocytes will be processed from peripheral blood to evaluate the biology of the virus infection and to determine the biologic effects of the interferon on the monocyte itself. Monoclonal antibodies to the glycoprotein of CAEV will be made for neutralization tests. We will insert the cloned DNA of CAE virus into the vaccinia vector. This will then be used to immunize goats to test the efficacy of this procedure in inducing neutralizing antibodies.